CARS.COM — Self-driving cars are the future, and automakers are working to get there. But we found that few are taking the same path — or even using similar terminology — on the way to autonomous cars.
Related: Self-Driving Cars: The Big List of Which Automakers Do What
We reached out to every major automaker to find out where each stands on the National Highway Traffic Safety Administration's five-level classification system for self-driving car technology, but most of them pushed back. As it turns out, much of the industry prefers a six-level alternative system from the Society of Automotive Engineers. SAE International's levels go like this:
- Level Zero means drivers still have to perform the dynamic task of driving at virtually all times, even if there are temporary warning or intervention systems. That means lane-departure, blind-spot and forward-collision warning systems — even those with automatic emergency braking — still are Level Zero by SAE standards. The same goes for lane departure prevention steering, which corrects your course only as you drift out of your lane, said Barbara Wendling, a Mercedes-Benz researcher who chairs the SAE's committee that helps develop autonomous-vehicle standards.
- Level 1 incorporates automatic acceleration and braking or automatic steering in specific driving modes but requires the driver to intervene as necessary and to operate the other tasks. Adaptive cruise control, true lane-centering steering that keeps you in the middle of your lane and automatic parking systems that steer you into a spot while you work the gas and brakes all are examples of Level 1, Wendling said.
- Level 2 incorporates automatic acceleration and braking along with lane-centering steering in certain cases but still requires the driver to monitor the road and other cars in order to to take over if necessary. In short, Level 2 systems can accelerate, decelerate and steer. Wendling noted that various current systems constitute Level 2, and it doesn't just have to be on the highway. A few park-assist steering systems also work the gas and brakes, qualifying for Level 2, though these are reasonably viewed as very different types of autonomy.
- Level 3 begins what SAE calls a legitimate "automated driving system" that controls all aspects of the driving task but still requires drivers to take over if necessary. Wendling said she's unaware of any automakers in the U.S. who currently offer Level 3 capabilities in a production car.
- Level 4 adds certain fallback capabilities so drivers don't have to intervene, but it still can't drive in all conditions. One Volkswagen official called Google's self-driving prototype an example of Level 4.
- Level 5 can drive itself in all conditions.
Confusion, Disagreement
Over weeks of written and verbal exchanges with 15 automakers, one thing became clear: There's plenty of disagreement — and even some outright confusion — on which levels represent what.
Some automakers' responses reflected conflicting interpretations of SAE levels. Others don't even want to use the standard. Officials at FCA and Hyundai-Kia said they prefer NHTSA's categories, while Ford, GM, Mercedes-Benz, Nissan, Toyota, Volkswagen and Volvo said they prefer SAE's categorization. BMW goes by the German Association of the Automotive Industry's automation standards. Honda and Mazda, meanwhile, said they have no official preference.
"We're finding that when we ask what we thought was a fairly straightforward question in that area to engineers ... they don't feel like we need to fit into a [classification] scheme," Toyota spokeswoman Cindy Knight said. And GM's John Capp, director of advance safety, said he didn't think any given model of car should receive an SAE "level" of autonomy at all, as SAE's classifications describe features, not cars.
Features Vary
The capabilities that constitute Level 1 or Level 2 technology are anything but uniform. Many adaptive cruise-control systems work only at highway speeds, but some operate all the way down to a full stop.
The same variations apply to lane-centering steering: Different systems have different characteristics. The Honda Civic's Lane Keeping Assist can help keep the car reasonably centered in its lane but doesn't work below 45 mph. Volvo's Pilot Assist feature on the 2016 XC90, by contrast, applies lane-centering steering only up to 30 mph.
And, of course, there's the issue of just how well each system works. Cars.com editors evaluate plenty of vehicles with self-driving technology, and a significant gap exists between the best and the worst. Good systems keep your car centered and properly spaced; bad ones allow too much meandering, even with well-marked lanes, and react to slowing or merging traffic with all the smoothness of a first-time driver.
Some drivers think they have a lane-centering system when, in fact, it's just a lane-keeping one designed only to react when the car wanders outside the lines — the sort that SAE's Wendling doesn't even consider part of the hierarchy.
"The lane keeping aid can keep you in the lane, but it doesn't mean you should use it regularly as a function to keep you in the lane," Volvo spokesman Jim Nichols said. "What you're doing is using a safety system as a convenience function, and that's not what it's designed to do."
For consumers, the names of such systems complicate matters even more. Mazda says its Lane-Keep Assist in the redesigned CX-9 is not a lane-centering system. GM said its widely offered Lane Keep Assist does not center the car, either.
Yet other systems that do center the car have virtually the same names. Honda says its system, dubbed Lane Keeping Assist, does center the car. And Lexus refers to its lane-centering steering as Lane Keep Assist — letter for letter, the same name as GM's system that doesn't center the car.
Hands-Free? Not Really
Then there's the issue of hands on the wheel — a concept that may seem antithetical to the idea of a self-driving car. The vast majority of today's Level 2 cars all but require it, courtesy of aggressive timeouts on their lane-centering steering. You have to touch the wheel every few seconds in the BMW 7 Series for the lane-centering steering to keep functioning. Audi sets its timeouts at 8 seconds. For Volvo, it's as long as 15 seconds.
Mercedes' Christian Bokich told us the automaker's redesigned E-Class, which goes on sale this summer, will reach Tesla-like levels of automation with automated lane changes and self-driving for up to 60 seconds before you have to touch the wheel, conditions permitting.
Still, at least one automaker argues that these timeouts should disqualify any lane-centering steering system from Level 2 at all.
"To be truly a Level 2 system, the system has to be, by design, a hands-off system," said Andy Christensen, a senior manager of Intelligent Transportation Systems Research at Nissan's Technical Center North America. He calls that "sustained control."
Nissan appears to be an outlier on the topic. When asked about the timeouts, an SAE spokesman didn't respond. But multiple automakers said their understanding of SAE's automation standards is that they don't stipulate hands-off for Level 2.
Either way, hands-free steering in affordable cars could come soon.
Hyundai's Cason Grover, a senior group manager in Hyundai's vehicle planning division, thinks the industry is "getting close" to having mass-market lane-centering steering systems that don't require driver involvement — similar to Tesla's Autopilot.
"As more cars have sensors and sensors improve, we can rely on them more completely," he said. But "you have to have a breakthrough in driver trust, and one of the things that the car is going to have to do is give you a good sense that it knows what's going on."
from Cars.com News http://ift.tt/1UiXFZH
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